The 2016 CACREP Standards call for the formal assessment of student professional dispositions throughout a counselor education program. This is a complex and often unwelcome task for faculty given the subjective nature of assessing non-academic competencies. Furthermore, considering the ethical and legal implications of this task, an empirically-based instrument would benefit faculty in counselor education programs in a variety of ways including ensuring due process during evaluations. Using a two-phase methodology, the current study began with a Delphi panel to establish items to be included in an instrument. The second phase involved validation of the instrument items using a survey distributed to Certified Rehabilitation Counselors (n = 148). Instrument items were rated on Relevance and Utility to assess their appropriateness for being included in the instrument. The Assessment as Growth Inventory (AGI), was developed, being framed using the working alliance in order to encourage the development of student professional dispositions in line with this evidence-based practice. AGI comprises four sections, with 48 items (Professional Dispositions--13, Tasks--10, Goals--8, and Bonds--17). Implications for research, counselor education, and clinical practice are discussed at length. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]